April 19 2017 was sunny and mild.
Overnight, 19/20th, temperature dropped below freezing and we had 1" of new snow,
Found this 'barely-alive' bee on a dry spot on our deck.
Brought it indoors but it never recovered. Took a look under a lens and saw it was heavily infested with mites. Killed the mites with alcohol.

Top: bee after alcohol treatment
bottom: mites that washed off in the alcohol.
I have seen many mite-infested insects but don't recall ever seeing this many on one insect.

I believe the bee is a solitary, soil-dwelling Halicitid Bee.
Will clean up the poor bee and take a closer look at the mites.

63mm El-Nikkor enlarging lens, f/4, D90, Zerene stack for top image.
_________________NU.
student of entomology
Quote – Holmes on ‘Entomology’
” I suppose you are an entomologist ? “
” Not quite so ambitious as that, sir. I should like to put my eyes on the individual entitled to that name.
No man can be truly called an entomologist,
sir; the subject is too vast for any single human intelligence to grasp.”
Oliver Wendell Holmes, Sr
The Poet at the Breakfast Table.

I cleaned the bee as best I could.
Family: Megachilidae; Osmia sp. (Mason Bee).

The mites were 6-legged nymphs and as such not structurally interesting.
_________________NU.
student of entomology
Quote – Holmes on ‘Entomology’
” I suppose you are an entomologist ? “
” Not quite so ambitious as that, sir. I should like to put my eyes on the individual entitled to that name.
No man can be truly called an entomologist,
sir; the subject is too vast for any single human intelligence to grasp.”
Oliver Wendell Holmes, Sr
The Poet at the Breakfast Table.

What a spectacle! The look mostly unattached, like they are just hitching a ride, as Rik suggested. Lots of mites live in flowers and get from flower to flower by riding on bees and butterflies and hummingbirds. But I've never seen such a crowd!_________________Lou Jost
www.ecomingafoundation.wordpress.comwww.loujost.com

I have seen mites on insects that have been very firmly attached. These mites were not attached, except to the hairs and each other, and appear to be phoretic.

Top: ventral brightfield
bottom: ventral,polarized showing very bright spots at base of claws and in the body.

Both: Oly BH2/BHS. 10xx + 1.25x + 2.5x NFK; Zerene stacks
_________________NU.
student of entomology
Quote – Holmes on ‘Entomology’
” I suppose you are an entomologist ? “
” Not quite so ambitious as that, sir. I should like to put my eyes on the individual entitled to that name.
No man can be truly called an entomologist,
sir; the subject is too vast for any single human intelligence to grasp.”
Oliver Wendell Holmes, Sr
The Poet at the Breakfast Table.